[thelist] Small Type

What is the smallest type spec that will render legibly in most browsers?
I have used Helvetica-Arial-Sans in size=2 or size=-1 for things I
want people to be able to read or
Helvetica-Arial-Sans in size=8pt
but these do not render well in Mac Netscape Navigator 4.7 or in some
older PC browsers.
What do folks suggest for:
- Type no one really reads (e.g. legal boilerplate)
- Type you want people to be able to read but with minimal legible size?